Modes of delivery of genetic testing services and the uptake of cancer risk management strategies in BRCA1 and BRCA2 carriers.

BRCA testing services are now offered by various healthcare providers, thus it is important to evaluate whether the implementation of cancer risk management (CRM) strategies varies by service provider. Using a registry-based sample of 795 female BRCA mutation carriers, we explored the association between uptake of CRM strategies with duration of genetic counseling (GC) sessions, provider type, and other demographic and clinical variables. All participants completed a baseline questionnaire. Information about uptake of CRM strategies was collected for a subset of 438 participants who completed additional questions. Summary statistics and Pearson chi-squared analysis were used to examine the associations between demographic and clinical variables with service delivery factors and with the uptake of various CRM strategies. Overall uptake of CRM strategies was high across all provider types. However, GC sessions were longer when provided by a genetics professional than by another provider (p < 0.001). Furthermore, higher frequencies of uptake of most CRM strategies were associated with longer GC sessions and when testing was performed by a genetics professional. Identification of factors to optimize delivery of these specialized GC services is important to maximize implementation of CRM strategies in BRCA carriers.

Mutation analysis of the BRCA2 gene in 49 site-specific breast cancer families.

The hereditary breast cancer gene BRCA2 was recently cloned and is believed to account for almost half of site-specific breast cancer families and the majority of male breast cancer families. We screened 49 site-specific breast cancer families for mutations in the BRCA2 gene using single strand conformation analysis (SSCA) followed by direct sequencing. We found mutations in eight families, including all four families with male breast cancer. The eight mutations were small deletions with the exception of a single nonsense mutation, an all were predicted to interrupt the BRCA2 coding sequence and to lead to a truncated protein product. Other factors which predicted the presence of a BRCA2 mutation included a case of breast cancer diagnosed at age 35 or below (P = 0.01) and a family history of pancreatic cancer (P = 0.03). Two mutations were seen twice, including a 8535delAG, which was detected in two French Canadian families. Our results suggest the possibility that the proportion of site-specific breast cancer families attributable to BRCA2 may be overestimated.

BRCA2 mutations in primary breast and ovarian cancers.

The second hereditary breast cancer gene, BRCA2, was recently isolated. Germline mutations of this gene predispose carriers to breast cancer, and, to a lesser extent, ovarian cancer. Loss of heterozygosity (LOH) at the BRCA2 locus has been observed in 30-40% of sporadic breast and ovarian tumours, implying that BRCA2 may act as a tumour suppressor gene in a proportion of sporadic cases. To define the role of BRCA2 in sporadic breast and ovarian cancer, we screened the entire gene for mutations using a combination of techniques in 70 primary breast carcinomas and in 55 primary epithelial ovarian carcinomas. Our analysis revealed alterations in 2/70 breast tumours and none of the ovarian carcinomas. One alteration found in the breast cancers was a 2-basepair (bp) deletion (4710delAG) which was subsequently shown to be a germline mutation, the other was a somatic missense mutation (Asp3095Glu) of unknown significance. Our results suggest that BRCA2 is a very infrequent target for somatic inactivation in breast and ovarian carcinomas, similar to the results obtained for BRCA1.

In vitro analysis of ovarian cancer response to cisplatin, carboplatin, and paclitaxel identifies common pathways that are also associated with overall patient survival.

BACKGROUND: Carboplatin and cisplatin, alone or in combination with paclitaxel, have similar efficacies against ovarian cancer (OVCA) yet exhibit different toxicity profiles. We characterised the common and unique cellular pathways that underlie OVCA response to these drugs and analyse whether they have a role in OVCA survival. METHODS: Ovarian cancer cell lines (n=36) were treated with carboplatin, cisplatin, paclitaxel, or carboplatin-paclitaxel (CPTX). For each cell line, IC(50) levels were quantified and pre-treatment gene expression analyses were performed. Genes demonstrating expression/IC(50) correlations (measured by Pearson; P<0.01) were subjected to biological pathway analysis. An independent OVCA clinico-genomic data set (n=142) was evaluated for clinical features associated with represented pathways. RESULTS: Cell line sensitivity to carboplatin, cisplatin, paclitaxel, and CPTX was associated with the expression of 77, 68, 64, and 25 biological pathways (P<0.01), respectively. We found three common pathways when drug combinations were compared. Expression of one pathway ('Transcription/CREB pathway') was associated with OVCA overall survival. CONCLUSION: The identification of the Transcription/CREB pathway (associated with OVCA cell line platinum sensitivity and overall survival) could improve patient stratification for treatment with current therapies and the rational selection of future OVCA therapy agents targeted to these pathways.

Cyclooxygenase-2 (COX-2) expression in human endometrial carcinoma and precursor lesions and its possible use in cancer chemoprevention and therapy.

In recent years, the design of new antineoplastic agents that can halt the progression of human malignancies with minimal systemic damage has been at the forefront of cancer research, with cyclooxygenase-2 (COX-2) as a major target molecule. With an aim to demonstrate the expression and role of COX-2, the principal putative target of COX-2 inhibitor therapy, in endometrial adenocarcinoma (EACA) and precursor lesions, atypical complex hyperplasia (ACH) and endometrial hyperplasia (EH), an immunohistochemical (IHC) analysis of 22 primary human EACAs and 14 precursor lesions was carried out. Relevant clinicopathological data were tabulated from a random computer-generated sample of 22 primary EACA patients, treated by hysterectomy at our institution. Representative tumor sections including adjacent precursor lesions and normal endometrium (NE) were immunostained with human monoclonal anti-COX-2. Qualitative and semi-quantitative COX-2 IHC staining scores were determined based on the proportion of immunoreactive cells and the intensity of cytoplasmic COX-2 expression. Fisher's exact test and the Wilcoxon Rank Sum test were used for statistical analysis. Mean patient age was 68 years (range 51-93). All 22 EACAs were of endometrioid type, of which ten (45%) were grade I, eight (36%) grade II and four (18%) were grade III. Overall, four out of nine (44%) EHs, four out of five (80%) ACHs, and 18 out of 22 (88%) EACAs were COX-2 positive. The mean COX-2 IHC scores for EH and EACAs were 33 (SD 24.11) and 76 (SD 54.57), respectively (p = 0.022). Strong or moderate COX-2 expression was observed in 17 out of 22 (77%) adenocarcinomas as compared to two out of 14 (14%) of the precursor lesions (EH and ACH). The areas of adenomyosis were COX-2 positive, while myometrial smooth muscle and normal fallopian tube tissues stained negative for COX-2. The demonstration of frequent and strong expression of COX-2 in human EACAs supports a possible role for COX-2 inhibitors. Furthermore, an increasing expression of COX-2 from EH to invasive EACAs suggests potential usefulness of COX-2 inhibition to halt the progression of precursor lesions to invasive endometrial cancers.

Frequency of germline and somatic BRCA1 mutations in ovarian cancer.

Germline mutations in the BRCA1 tumor suppressor gene are thought to be the most common cause of hereditary ovarian cancer. The aim of this study was to explore further the role of BRCA1 alterations in the development of ovarian cancers. We sought to determine whether somatic BRCA1 mutations are ever present in ovarian cancers and whether mutation is always accompanied by loss of the wild-type allele. The entire coding region and intronic splice sites of BRCA1 were sequenced using genomic DNA samples from 103 unselected ovarian cancers. Thirteen clearly deleterious BRCA1 mutations and two variants of uncertain significance were found. Blood DNA was available in all but two cases and demonstrated that 4 of 13 mutations and both variants of uncertain significance were germline alterations, whereas in seven cases the mutation was a somatic change present only in the cancer. Using four microsatellite markers, loss of heterozygosity at the BRCA1 locus was found in all 15 ovarian cancers with BRCA1 sequence alterations, compared with only 58% of ovarian cancers that did not have BRCA1 mutations. BRCA1-associated ovarian cancers were characterized by serous histology and moderate histological grade. These data confirm prior reports suggesting that germline mutations in BRCA1 are present in about 5% of women with ovarian cancer. In addition, somatic mutations in BRCA1 occur in the development of some sporadic cases. The finding that both germline and somatic BRCA1 mutations are accompanied by loss of heterozygosity, suggests that loss of this tumor suppressor gene is a critical event in the development of these cancers.

Desmethylimipramine potentiates NMDA responses in a mouse cortical slice preparation.

Desmethylimipramine (DMI) has been shown to interact with the N-methyl-D-aspartate (NMDA) receptor complex. Its probable action is through blockade of the cationic channel at the phencyclidine site and as a result it has potential anticonvulsant action. In this present study we have investigated the effects of DMI and ketamine on both NMDA-induced and spontaneous depolarizing shifts in cortical wedges prepared from genetically epilepsy-prone mice (DBA/2). Contrary to published reports, DMI potentiated the effects of NMDA and increased the frequency of spontaneous depolarizations. The actions of ketamine were inhibitory and these were reversed by DMI. Presynaptic mechanisms may be involved in the DMI-induced potentiation and this may explain the lowering of convulsive thresholds seen clinically with tricyclic antidepressants.

An inevitable dilemma: prenatal testing for mutations in the BRCA1 breast-ovarian cancer susceptibility gene.

The BRCA1 breast-ovarian cancer susceptibility gene was identified recently. Germline mutations in BRCA1 may be responsible for as many as 5% of breast and ovarian cancers. Inherited alterations confer up to a 94% risk of developing breast and/or ovarian cancer by age 70. With the discovery of BRCA1, there will be a heavy demand for genetic testing. Because of the large size of the gene and the distribution of reported mutations, scientists face considerable technical problems in developing widely available screening tests; clinicians will face even greater ethical problems in applying them. In the context of research programs, women with BRCA1 mutations are already being identified, and their physicians are confronted with a number of complex medical, ethical, legal, and social issues. Obstetricians will be faced with counseling parents regarding prenatal testing for specific BRCA1 mutations. Although it is difficult to formulate straightforward guidelines regarding prenatal BRCA1 testing, clinicians and health care providers must be familiar with the nuances of the debate so that these issues can be discussed wisely with patients. As with many ethically challenging problems in medicine, individual clinicians and their patients will have to work together to determine the course of action with which they are most comfortable. Although elective termination of a pregnancy with a germline mutation in BRCA1 is an option, experience with other adult-onset diseases suggests that only a minority of parents will choose this option.

Aberrant splicing of the TSG101 tumor suppressor gene in human breast and ovarian cancers.

OBJECTIVE: To determine whether large deletions or other alterations in the putative tumor suppressor gene TSG101 play a role in the molecular pathogenesis of breast and ovarian cancers. METHODS: Expression of TSG101 transcripts was examined in breast and ovarian cancers using the reverse transcriptase-polymerase chain reaction (RT-PCR), and selected transcripts were sequenced. Southern blot analysis was performed to determine whether there were genomic deletions in the TSG101 gene, and Northern blot analysis was used to examine the relative abundance of various transcripts. RESULTS: All the cancerous and normal breast tissue examined expressed full length 1145 base pair (bp) TSG101 transcripts. Additional truncated transcripts were seen using the RT-PCR in 57 (64%) of 89 primary breast cancers, 1 (20%) of 5 breast cancer cell lines, 3 (50%) of 6 normal breast tissues, 16 (64%) of 25 primary ovarian cancers and 1 (33%) of 3 ovarian cancer cell lines. Only the primary breast (21%) and ovarian (24%) cancers had three or more truncated transcripts. None of the normal tissues or cell lines examined had more than two aberrant transcripts. DNA sequencing revealed that the most commonly expressed truncated transcript arises because of loss of 902 bp between codons 153 and 1055. Only full length TSG101 transcripts were seen on Northern blot analysis of breast cancer cell lines, however. There was no evidence of genomic deletions in the TSG101 gene on Southern blot analysis. CONCLUSION: Truncated TSG101 transcripts that probably represent splice variants are present in some breast and ovarian cancers, but there is no evidence to suggest that loss of this putative tumor suppressor gene plays a role in the molecular pathogenesis of these cancers.

Intraspinal pathways taken by sublaminar wires during removal. An experimental study.

The neurological complications of segmental sublaminar stabilization that have been reported by other authors led us to perform a cineradiographic study of the pathways in the spinal canal that were taken by wires as they were being removed. The single wires were removed by pulling on the wire while keeping the wire perpendicular to the lamina; by winding the wire on the wire-extractor, with the wire being kept as nearly parallel with the lamina as possible (the roll-up technique); or by pulling on the wire while keeping the wire parallel with the lamina. During removal, thirty-four single wires conformed to the lamina and forty-one single wires compressed the dura. The roll-up technique caused the most erratic pathways. Double wires, although they were removed together, assumed independent pathways unless a wire-extractor guide was used. These findings suggest that the removal of sublaminar wires may cause dural compression in the clinical situation.

Upregulation of miRNA-155 promotes tumour angiogenesis by targeting VHL and is associated with poor prognosis and triple-negative breast cancer.

MicroRNA-155 (miR-155) is frequently upregulated in various types of human cancer; however, its role in cancer angiogenesis remains unknown. Here, we demonstrate the role of miR-155 in angiogenesis through targeting von Hippel-Lindau (VHL) tumour suppressor in breast cancer. Ectopic expression of miR-155 induced whereas knockdown of miR-155 inhibited human umbilical vein endothelial cell network formation, proliferation, invasion and migration. Furthermore, mammary fat pad xenotransplantation of ectopically expressed miR-155 resulted in extensive angiogenesis, proliferation, tumour necrosis and recruitment of pro-inflammatory cells such as tumour-associated macrophages. Expression of VHL abrogated these miR-155 effects. Moreover, miR-155 expression inversely correlates with VHL expression level and is associated with late-stage, lymph node metastasis and poor prognosis, as well as triple-negative tumour in breast cancer. These findings indicate that miR-155 has a pivotal role in tumour angiogenesis by downregulation of VHL, and provide a basis for miR-155-expressing tumours to embody an aggressive malignant phenotype, and therefore miR-155 is an important therapeutic target in breast cancer.

Defining practice patterns in gynecologic oncology to prevent pulmonary embolism and deep venous thrombosis.

OBJECTIVE: The goal of venous thromboembolism (VTE) prophylaxis is to reduce the morbidity and mortality associated with the development of a deep venous thrombosis (DVT) or pulmonary embolism (PE). Because women with gynecologic cancers are at high risk to develop VTE, we sought to determine the present practice patterns of gynecologic oncologists regarding their use of VTE prophylaxis. METHODS: 1073 members of the Society of Gynecologic Oncologists (SGO) were mailed surveys that asked about preferred methods to prevent the development of VTE after gynecologic oncology surgery. Data were collected by online member entry and return mail. Frequency distributions were calculated and nonparametric test used for comparisons. RESULTS: 343/1073 (34%) of SGO members and fellows responded. 142/343 (42%) preferred double prophylaxis consisting of external pneumatic compression (EPC) and an anticoagulant while 41% (n=141) preferred EPC with no additional anticoagulation. Of respondents choosing any anticoagulant, 40% preferred Enoxaparin pre- and/or postoperatively. Ovarian cancer patients were perceived by respondents to have the highest risk of developing a postoperative PE. CONCLUSIONS: Most respondents agree that women with gynecologic cancers undergoing major surgery should receive VTE prophylaxis, though there is not agreement as to which method is optimal. While 42% of members preferred double prophylaxis, 41% chose no additional measures other than EPC. Randomized studies in gynecologic oncology should be initiated in the United States to determine the optimal practice pattern.

High expression of insulin-like growth factor binding protein-2 messenger RNA in epithelial ovarian cancers produces elevated preoperative serum levels.

The molecular etiology of epithelial ovarian cancer remains unclear. Using microarray expression analysis, we recently reported that expression of the insulin-like growth factor binding protein-2 (IGFBP-2) gene is elevated in advanced epithelial ovarian cancers. The aim of this study was to further delineate the role of IGFBP-2 in the pathoetiology of epithelial ovarian cancer and determine if elevated ovarian cancer IGFBP-2 gene expression is reflected in serum. Relative IGFBP-2 expression was measured using quantitative real-time polymerase chain reaction in 113 epithelial ovarian cancers and 6 normal ovarian surface epithelial samples. Preoperative serum IGFBP-2 levels were measured by radioimmunoassay in 84 women (42 ovarian cancers, 26 benign gynecological conditions, and 10 healthy female controls). Ovarian cancers demonstrated 38-fold higher mean IGFBP-2 expression than normal ovarian epithelium (P < 0.01). Serum IGFBP-2 levels were elevated in women with early- and advanced-stage ovarian cancer compared to controls and patients with benign gynecological conditions (P = 0.05 and P < 0.01, respectively). Epithelial ovarian cancers express high levels of IGFBP-2 relative to normal ovarian epithelium, and this is associated with elevated serum IGFBP-2 levels compared to both normal controls and patients with benign gynecological disease. Our findings provide further support that the insulin-like growth factor pathway plays a significant role in epithelial ovarian cancer pathogenesis. Further, IGFBP-2 may represent an additional serum biomarker with utility in detection and monitoring of epithelial ovarian cancer.

Identification of genes associated with ovarian cancer metastasis using microarray expression analysis.

Although the transition from early- to advanced-stage ovarian cancer is a critical determinant of survival, little is known about the molecular underpinnings of ovarian metastasis. We hypothesize that microarray analysis of global gene expression patterns in primary ovarian cancer and metastatic omental implants can identify genes that underlie the metastatic process in epithelial ovarian cancer. We utilized Affymetrix U95Av2 microarrays to characterize the molecular alterations that underlie omental metastasis from 47 epithelial ovarian cancer samples collected from multiple sites in 20 patients undergoing primary surgical cytoreduction for advanced-stage (IIIC/IV) serous ovarian cancer. Fifty-six genes demonstrated differential expression between ovarian and omental samples (P < 0.01), and twenty of these 56 differentially expressed genes have previously been implicated in metastasis, cell motility, or cytoskeletal function. Ten of the 56 genes are involved in p53 gene pathways. A Bayesian statistical tree analysis was used to identify a 27-gene expression pattern that could accurately predict the site of tumor (ovary versus omentum). This predictive model was evaluated using an external data set. Nine of the 27 predictive genes have previously been shown to be involved in oncogenesis and/or metastasis, and 10/27 genes have been implicated in p53 pathways. Microarray findings were validated by real-time quantitative PCR. We conclude that gene expression patterns that distinguish omental metastasis from primary epithelial ovarian cancer can be identified and that many of the genes have functions that are biologically consistent with a role in oncogenesis, metastasis, and p53 gene networks.

Carbamazepine inhibits NMDA-induced depolarizations in cortical wedges prepared from DBA/2 mice.

There is some doubt as to the mechanism of action of the widely-used anticonvulsant drug, carbamazepine. In cortical wedges prepared from genetically epilepsy-prone DBA/2 mice, carbamazepine at therapeutic concentrations (1-10 microM) markedly reduced the depolarization produced by N-methyl-D-aspartate (NMDA). The NMDA sub-type of glutamate receptor has been implicated in the pathogenesis of epilepsy and the inhibitory action of carbamazepine on this response suggests that the anticonvulsant action of the drug may be due to its blockade of NMDA receptor-mediated events.

Dideoxy fingerprinting assay for BRCA1 mutation analysis.

Since the isolation of BRCA1, the familial breast/ovarian cancer predisposition gene, much effort has been invested in characterizing the mutation spectrum. The large size of the gene and the wide distribution of its more than 100 mutations has increased the challenge of this endeavor such that traditional mutation detection techniques are inadequate. We examined the sensitivity of dideoxy fingerprinting (DDF), which combine a Sanger sequencing reaction with multiple-fragment single-strand conformation analysis (SSCA), as a mutation detection technique to screen BRCA1. Here we describe the technique and compare its sensitivity with that of SSCA in detecting 21 previously described BRCA1 sequence variants. All the variants were detected by DDF, but only 17 of 21 (81%) were observed by SSCA under standard conditions. Three of four alterations missed by SSCA were base substitutions. As a BRCA1 mutation detection technique, DDF was more sensitive than SSCA and may prove to be a useful research tool in defining the mutation spectrum within this and other genes.

Mutational analysis of the PTEN gene in human uterine sarcomas.

OBJECTIVE: Uterine sarcomas are rare, lethal cancers, and little is known about their molecular etiology. The PTEN gene is located on chromosome 10q23.3, a region that displays frequent loss of heterozygosity in human uterine sarcomas. PTEN mutations have been described in 40% to 60% of uterine adenocarcinomas. To determine whether the PTEN gene is involved in the pathogenesis of uterine sarcoma, we analyzed deoxyribonucleic acid from uterine sarcomas and cell lines. STUDY DESIGN: Single-strand conformation analysis and direct sequencing of deoxyribonucleic acid were used to screen for PTEN mutations. RESULTS: Silent polymorphisms were detected in 2 of 36 primary uterine sarcomas. A 4-base pair deletion and a point mutation producing a stop codon were identified in 1 cell line. CONCLUSIONS: Mutational inactivation of PTEN does not play a major role in uterine sarcoma tumorigenesis, and another gene or genes on chromosome 10q may be implicated as a cause of these cancers. Differences in the molecular alterations underlying the development of uterine sarcomas and adenocarcinomas are significant.

Role of BRCA1 mutation screening in the management of familial ovarian cancer.

Families with multiple cases of ovarian cancer have long been observed, and in the past prophylactic oophorectomy has been advocated for women with a history of ovarian cancer in two first-degree relatives. It is now thought that > 90% of familial ovarian cancer is due to inherited mutations in the BRCA1 breast-ovarian cancer susceptibility gene on chromosome 17q. BRCA1 testing is being performed in several academic medical centers on a research basis and is also now commercially available. With the ability to identify inherited mutations in BRCA1, prophylactic oophorectomy and other interventions intended to decrease cancer mortality can be offered specifically to women who carry a mutation, but the optimal strategy for decreasing cancer mortality in BRCA1 families has not yet been determined. To facilitate further clinical and basic research in this field, our group and others have established multidisciplinary hereditary breast-ovarian cancer clinics that offer a wide range of services including BRCA1 testing, genetic counseling, and cancer prevention and treatment.

Pathologic fractures of the humerus.

In a study of 57 actual or impending pathologic fractures of the humerus in 52 patients with inoperable cancer treated between 1972 and 1982, we retrospectively reviewed the charts for analysis and comparison of the functional result and pain relief afforded by the various treatments used. Function of the extremity and relief of pain were each graded as excellent, good, fair, or poor using a modification of Perez's rating system. Seven pathologic fractures were treated nonoperatively. These patients generally had only fair pain relief and a poor functional result. Forty-six pathologic fractures were treated with intramedullary fixation using a Rush rod (n = 16), a Küntscher rod (n = 29), or an Ender rod (n = 1); the Neer endoprosthesis was used in four patients. Thirty-one patients received radiation to the humerus. There were seven operative complications, the most common (n = 3) being prominence of an intramedullary rod at the insertion site which required a second minor procedure for advancement of the rod. From this series, we conclude that any patient who has a pathologic fracture or impending fracture of the humerus and a predicted survival of six weeks or more is likely to benefit from rigid internal fixation with an appropriately selected device, adjunctive use of methylmethacrylate, and postoperative local irradiation therapy as needed.